The George C. Marshall Institute (GMI) was established in 1984 in Washington, D.C. "to conduct technical assessments of scientific issues with an impact on public policy". It is known for its skepticism toward the mainstream scientific opinion on climate change, and its strong support for the Strategic Defense Initiative. It is one of only a few conservative think tanks engaged in environmental policy debates to have natural scientists on staff. The institute is named after World War II military leader and statesman George C. Marshall.
Historian Naomi Oreskes says the institute has, in order to resist and delay regulation, lobbied politically to create a false public perception of scientific uncertainty over the negative health effects of second-hand smoke, the carcinogenic nature of tobacco smoking, and on the evidence between CFCs and ozone depletion.
Noted skeptics Sallie Baliunas and (until his recent death) Frederick Seitz (a past President of the National Academy of Sciences from 1962 - 1969) are on its Board of Directors, Patrick Michaels is a "visiting scientist" and Stephen McIntyre, Willie Soon and Ross McKitrick are "contributing writers". Richard Lindzen served on the Institute's Science Advisory Board. Four members of GMI's Board of Directors have been involved with SEPP. GMI is a former member of the Cooler Heads Coalition.
In 1998 Jeffrey Salmon, then executive director of GMI, helped develop the American Petroleum Institute's strategy of stressing the uncertainty of climate science. In February 2005 GMI co-sponsored a Congressional briefing at which Senator James Inhofe praised Michael Crichton's novel State of Fear and attacked the "hockey stick graph".
Responding to the GMI's criticism of the Arctic Climate Impact Assessment, Senator John McCain (R-AZ) stated, "General Marshall was a great American. I think he might be very embarrassed to know that his name was being used in this disgraceful fashion.
GMI used to restrict its funding sources to private foundations and individual donors, but in 1999, Salmon wrote that "Fifteen years of experience with a policy of refusing grants from industry has taught us that our reasons for adopting this restriction were both right and wrong. We were right about it costing us money. But we were wrong to think the policy would permit us to avoid the charge of being a corporate funded think-tank." He said that "the positions we had taken over the last decade and a-half were so crystal-clear that it would be absurd to claim that the Marshall Institute was tailoring its position to fit the needs of some corporate interest", and accordingly, "From now on the Marshall Institute will accept grants for general program support from corporate foundations and in some cases directly from corporations. The Board has also determined that before we accept a grant it must be clear to us that the corporate foundation or corporation offering us funding must have a prior record of supporting well-known environmental groups, or groups with a record of opposing the deployment of ballistic missile defenses.
In 1999, GMI received grants from the Exxon Education Foundation. The institute's CEO William O'Keefe, formerly an executive at the American Petroleum Institute and chairman of the Global Climate Coalition, is a registered lobbyist for ExxonMobil. The GMI was described in a 2007 report by the Union of Concerned Scientists as an ExxonMobil-funded "clearinghouse for global warming contrarians". ExxonMobil still currently provides funds to the Institute .
William O'Keefe, chief executive officer of the Marshall Institute, and once Executive Vice President and Chief Operating Officer of the American Petroleum Institute, questions the methods used by advocates of new government restrictions to combat global warming.